Regardless of the decanting principle used for the viscous substance, including e.g. piston dosage, membrane technology, pressure-dependent, time-regulated dosage for a prespecified pressure chamber characteristic, inductive discharge measurement, weight dosage in a storage container placed on weighing meters, and similar techniques, the decanted material (also primarily described as viscous material) may be cut between a filling mechanism (also primarily described as a portioning device) and a decanting container. This cutting of the decanted material has traditionally been achieved e.g. by means of a cylindrical filling pipe with a valve face at its exit point.
This filling pipe is sealed by means of a slide acting as a counterpart either in the outflow direction or conversely at the end of a dosage operation, thus cutting the decanted material. An alternative cutting technique is known in the form of the rotary disk principle, in which a rotating valve plug seals the dosage path, and vice versa. The adhesion/cohesion between the filling pipe and the product is also suitable for cutting the decanted material, which obviates the need for cutting the material after the end of the dosage stroke. This known principle can be supported by blowing the material free with air or inert gas. As an alternative, gravity can be used to achieve a reproducible emptying of the filling pipe.
Rotating circular blades or special blade sections, which are moved transversely to the flow direction of the decanted material, could also be used as cutting devices for the decanting equipment under discussion.
Independent of the aforementioned cutting principles, essential prerequisites for the cutting operation are that it is reproducible, that the cutting occurs without subsequent droplet formation, that no product threads are created, and that the cut portions siphon cleanly back into the filling pipe or the decanting container in order to ensure that the container is filled to the rim as desired. These conditions can be fulfilled by almost all of the aforementioned cutting devices, at least for low decanting speeds and low-viscosity material. The problem arises when larger cycle times are required and/or the decanted material has a higher viscosity. Particularly in the case of highly viscous material, the generation of product threads cannot be ensured by the traditional cutting devices.
A decanting system of the type initially described is known from DE 92 08 679 U1 or DE 92 17 784 U1. These known decanting systems each use mechanical devices to cut through the product string, with the devices arranged between the portioning device in the form of a filling pipe and a decanting container.
WO 94/13451 A1 describes a technique whereby cooled and coagulated hotmelt packages are cut using a laser. DE 39 04 287 A1 describes a device for cutting fluid-containing materials by means of a laser.